New data from the Medicines and Healthcare Regulatory Agency (MHRA) suggest valproate is still being prescribed for pregnant women in the UK, despite restrictions.
Regulations, introduced in April 2018, state valproate medicines must not be used in women and girls of childbearing potential unless the conditions of the Pregnancy Prevention Programme (PPP) are met and only if other treatments are ineffective or not tolerated.
The MHRA has been monitoring trends in the prescribing of valproate using primary care data from the Clinical Practice Research Datalink GOLD database (CPRD).
The data show that both new and repeat prescribing of valproate in girls and women of childbearing age and in pregnancy declined over the period January 2010 to December 2018. A slightly larger decline was observed in the rate of new valproate prescriptions, with no new initiations in adolescent girls in July-December 2018.
There was a general decline in the rate of valproate initiation in girls and women, with an overall decline of approximately 80 per cent reduction in new use in the second half of 2018 compared with the first half of 2010 (4.9 vs. 0.9 per 10,000 women aged 14-45 years, respectively).
The decline in prescribing was observed across conditions, with a decrease of 40 per cent, 49 per cent and 48 per cent for epilepsy, bipolar disorder and migraine, respectively, during the study period.
The data show valproate prescribing in pregnancy is still occurring and there were no significant changes in prescribing rates in pregnancy between 2017 and 2018. Of about 450,000 pregnancies detected in the CPRD between January 2010 and December 2018, women received a prescription for valproate in 374 pregnancies (0.083%).